The database refresh happens if any information on a sandisk player occurs. That change in information doesn't doesn't need to be an alteration to a file done by the user. If any of the processes associated with Windows Media Player read the files that may be enough to trigger the database refresh.

I've seen as many as 7 different WMP related processes that might address the player depending on which mode it's in and if there's any DRM content on the player. Trying to identify which of those processes will be called and killing them once a player is connected turned out to be impossible for me. There seem to be a number of variables that dictate which process will be called at connection.

When I thought I had killed them all WMP reactivated some of them when the PC was rebootedbooted. The database refreshes started again once those reactivated processes read the player.

The sandisk database refresh can drain significant amounts of battery, especially if there's embedded album art involved. I've seen a Clip Zip that was at 100% charge finish at 66% after a database refresh that took over 1 hr. 15 mins. That 1 hr. 15 min. database refresh occurred using the same set of files that refreshed in less than 7 minutes on a Clip+ and a original version V2 Fuze. The same tags that were clean enough for a relatively short database refresh on a Clip+ still took what I considered an unreasonable amount of time on a Clip Zip.

In exploring why it took so long I discovered that embedded AA is sometimes extracted to hidden system files. They're .jpg files extracted from the embedded album art. They're named "folder.alb.0.xxxx" and are the same size as whatever AA is embedded. If you change the extension to .jpg they display in a graphics viewer as the embedded art.

It seems that using the limited processing power of a portable player to extract and create those files takes a long time and uses up battery power at a much higher level than playing music. The screen is on during all the time of the database refresh and that would also cause significant loss of battery life.

One of the odd things is that one of the advantages that MTP transfer had in the past goes away on the Clip Zip. MTP has always been slower for me but that was usually made up by a much shorter database refresh. The overall time was usually a bit longer using MTP but the shorter database refresh time made it useful for some of the people I know that preferred the ease of making playlists on a MTP device.

On the Clip Zip MTP transfer has taken longer than MSC transfer but it hasn't shortened the database refresh when I've tried it. The same files that took 45 minutes to refresh using MSC still took 45 minutes using MTP.

One other thing, it may seems as if I'm saying all of this is locked in stone but I'm not. Any and all of this can change according to types of files used, size of files used, USB tranfer mode used, whether the files are dragged and dropped, if they are synced using software, which software is used to sync the files, the settings that software uses, encoding of the tags, operating system, version of operating system, version of WMP, if the files are synced to the internal or external memory and possibly even the phase of the moon.